Noob Questions about Rooting and Epic 4g Touch.

So I just got my Epic 4g Touch for Sprint and I really like it. I heard about rooting and flashing ROM's and I think I can do it and would like too. One of the things I've heard is that flashing a new ROM on your device can improve 3g speeds/signal strength. Is this true? What kind of ROM's are available for the Epic 4g Touch? Where do I need to go to get started? What are other benefits of rooting/flashing a new ROM? Any help you can give would be appreciated!Thanks guys!